The imposing 135-step staircase was inaugurated by Pope Benedict XIII during the 1725 Jubilee; it was released (thanks to French loans granted in 1721–1725) in order to connect the Bourbon Spanish embassy (from which the square takes its name) to the Church of Trinità dei Monti.

It was designed by Alessandro Specchi and Francesco De Sanctis after generations of long and glowing discussions about how to urbanize the steep slope on the side of the Pincian Hill in order to connect it to the church. The final key was the one proposed by Francesco De Sanctis: a great staircase decorated with many garden-terraces, splendidly adorned with flowers in spring and summer. 

The sumptuous, aristocratic staircase, at the summit of a straight sequence of streets leading down to the Tiber, was designed so that the scenic effects increase more and more while approaching to it. In effect, the creation of long, deep perspectives culminating in monumental wings or backdrops was typical of the great baroque architecture. The Spanish Steps were restored in 1995.